feat: Prep for moving tests into single integration suite

Sources/MQTTConnectionService/MQTTConnectionService.swift

@@ -19,19 +19,22 @@ public struct MQTTConnectionService: Service {
   /// to the MQTT broker and handles graceful shutdown of the
   /// connection.
   public func run() async throws {
+    try await mqtt.connect()
+
     try await withGracefulShutdownHandler {
-      try await mqtt.connect()
       for await event in try mqtt.connectionStream().cancelOnGracefulShutdown() {
         // We don't really need to do anything with the events, so just logging
         // for now.  But we need to iterate on an async stream for the service to
         // continue to run and handle graceful shutdowns.
         logger?.trace("Received connection event: \(event)")
       }
-      // when we reach here we are shutting down, so we shutdown
-      // the manager.
-      mqtt.shutdown()
     } onGracefulShutdown: {
       self.logger?.trace("Received graceful shutdown.")
+      shutdown()
     }
   }
+
+  public func shutdown() {
+    mqtt.shutdown()
+  }
 }